Trench-jack.



A. H. GLAYMIER.

TRENGH JACK.

APPLICATION FILED JAN. 27, 1913.

1,132,763 Patented Mar.23,1915.

WITNESSE-S: INW I if @W iM A TTORNE Y5 THE NORRIS PETERS CO PHOTO-LITHO,WASHINGTON, D. C.

TE s,

ESrA'rn; F to ADAM GLAYMIEB, FAKE, WIs'G S N- manners-anon Specificationof Letters Iatent.

Patented Mar.2 3, 1915.

Application filed January 27, 19.13. Serial No. 744,381.

To all whom it may concern Be itknown that I, ADAM H. CLAYMI R,

.a citizen of the United States, residing at H the town of Lake, countyof Milwaukee, and

State of Wisconsin, have inventednew and useful Improvements inTrench-Jacks, of

which the followingis a specification.

My invention relates ,tothat class of devices which are used for holdingthe curbing in position along the walls ofditches, sewer trenches andthelike, or in wells or other excavations.

The object of my invention is to provide a form of'jack for the abovestated uses,

which can be quickly adjusted in a supporting position and subsequentlyextended to apply a forcible pressure to the walls to be supported, andwhich cannot be accidentally dislodged, it being regarded 'as extremelyimportant that a jack of this kind should be absolutely reliable for thereason that fatalities may result in case of a failure of the jack toprovide the expected support for the walls. A 1

In the drawings-Figure 1 is an elevation of a jack embodying myinvention. Fig. 2 is an elevation of the same, part in longitudinalsection, and viewed at right angles to other end of the tube D, afitting G is employed which is provided with a sleeve flange 9 adaptedto enter the end of the tube D and a capping flange g fitting over thisend of the tube and bearing upon its exterior surface, thus forming aslip joint connection between the fitting and the tube D, the latterconstituting a hollow spacing member. The fitting G is provided withslots 71, through which levers J which support nut segments H may pass.The levers J are pivoted at I to outwardly pro ect1ngears I, formed onthe exterior wall of'the fitting G. The levers J may be oscillated uponthe pivot pins or fulcrums I to move the nut segments inwardly oroutwardly'into and out of engagement with the screw F hereinafterdescribed. Compressing springs The threaded K are interposed between theouter vends of the levers J and the wall of the fitting G, whereby theseends of said levers are normally pressed outwardly to push. the nutsegments inwardly with reference to the slots it. i

A, bearing head piece L is swiveled at L- upon a screw threadedadjusting bolt-F, said bolt being also provided with a nutE preferablyadapted to receivea spanner'wrench.

portion of the bolt F is adapted to passthrough the tubular fitting G tothe interior oflthe tube D, and the nut segments H are threaded'toengage the threads on the bolt F Said bolt threads are slightly undercutin the direction of the head L, whereby pressurev applied to the head,when the nut segments are engaged with the bolt threads, will cause saidnut segments to rigidly grip the bolt.

In operation, assuming that the device is to be used in a ditch or sewertrench, the

cap C is placed against one wall or curb,j

and the outer arms of levers J are pushed inwardly, said arms being sopositionedthat they can be both simultaneously grasped in one hand bythe operator. When thelevers J are thus pushed inwardly, the nutsegments H are retracted from the bolt F. Said bolt F may then be pulledout until the head piece L strikes the opposite wall of the trench orcurbing. The levers J arethen released and the wrench applied to the nutE, rotating the bolt in the direction to feed it outwardly in the nutsegments H until the desired pressure against the curb walls engaged bythe caps G and head L, issecured. As the pressure increases, the nutsegments H are securely gripped by the engaging bolt threads, owing tothe inclination of the undercut sidesof the threads.

It then becomes impossible to release the nut segments by pressing the.lever arms J inwardly, and the jack will therefore remain in positionand cannot be dislodged by accident. Even a violent blow upon one orboth of the outer arms of levers J will not cause a release of the boltfrom the nut segments. When it is desired to remove the jack, the wrenchis again applied to the nut E to rotate bolt F in the opposite directionuntil the longitudinal pressure is relieved, whereupon the outer arms oflevers J may be moved inwardly to permit of a free adjustment of thebolt F to any desired position. By having nut segments, which are rretractable, it is possible to extend the jack to any desired lengthwithout loss of time, and therefore, in case any weakness appears at anyportion of the curbing, a jack may be instantly applied and adjusted inposition.

The end cap C and swiveled head piece L constitute bearing plates, andthese will of course be made large enough to cover the desired area uponthe surfaces of the curbing to which they are applied. The levers J arepreferably parallel to the sides of the fitting G for convenience inactuating these levers and also to avoid objectionable laterallyprojecting arms or spurs. The fitting G is formed independently of thetube D for the reason that the fitting G can most conveniently be formedas a casting, and this can vbe used with tubes D of any desired length,or with tubes D of diiferent lengths, where by the same apparatus may beemployed for trenches of different widths by merely interchanging tubesD of difierent lengths.

1 claim- 1. A trench jack, including the combination with a jack screw,of a tubular fitting adapted to receive said screw, and provided with aset of outwardly projecting ears, a set of elbowed levers pivoted tosaid ears each with one arm projecting inwardly and adapted to bear uponthe fitting, and pro- Gopies of this patent may be obtained for fivecents each, by addressing the vided at its extremity with a screwengaging nut segment, and springs interposed between the other ends ofsaid levers and the fitting, said fitting having sufficient thicknessand strength to support the inwardly projecting arms of the elbowedlevers in close proximity to the screw whereby strain upon the pivotalconnection of said levers to the ears is almost wholly relieved.

2. A sewer trench jack, comprising the combination with head pieces,each adapted to bear upon the curbing of a trench, of a hollow spacingmember having one end in slip joint connection with one head piece, afitting in slip joint connection with the other end of said spacingmember and provided with slots in opposite sides thereof, a screw havingswivel connection with the other head piece and adapted to slide looselyin said fitting and spacing member, and a set of spring actuated leverspivoted to the fitting and projecting through the slots therein, theinner ends of said levers being threaded and constitutin nut se mentsada ted to engage the screw, substantially as described. In testimonywhereof I affix my signature in the presence of two witnesses.

ADAM H. GLAYMIER Witnesses:

LEVERETT C. WHEELER,

H. C. VAN RYN.

Commissioner oi Patents,

Washington, D. 0.

